Various types of gearboxes, such as automotive transmissions, differential cases, and power transfer units, generally require some sort of breather vent that allows the pressure between the gearbox and the external environment to equalize. Some breather vents incorporate filter media to prevent the ingress of contaminants such as dust and fluids to the gearbox. For example, a microporous membrane can be used to prevent the entry of water in the gearbox. Oil particles that are present in the gearbox, however, can become airborne and lodge into the membrane. Some existing technology uses an oil sorbent (e.g., absorbent and/or adsorbent of oil) filter media that is configured to capture the oil particles before they reach the membrane. However, such vents have a relatively short lifespan because, as the oil particles accumulate in the media, the media becomes clogged, which decreases the life of the vent. Furthermore, because the sorbent filter media wicks the oil particles, the oil can foul the membrane relatively quickly.
The present technology may be more completely understood and appreciated in consideration of the following detailed description of various embodiments in connection with the accompanying drawings.